气候变化领域集成服务门户(CCPortal): Soil Organic Matter Persistence as a Stochastic Process: Age and Transit Time Distributions of Carbon in Soils

CCPortal

DOI	10.1029/2018GB005950
	Soil Organic Matter Persistence as a Stochastic Process: Age and Transit Time Distributions of Carbon in Soils
	Sierra C.A.; Hoyt A.M.; He Y.; Trumbore S.E.
发表日期	2018
ISSN	0886-6236
EISSN	1944-9224
起始页码	1574
结束页码	1588
卷号	32 期号:10
英文摘要	The question of why some types of organic matter are more persistent while others decompose quickly in soils has motivated a large amount of research in recent years. Persistence is commonly characterized as turnover or mean residence time of soil organic matter (SOM). However, turnover and residence times are ambiguous measures of persistence, because they could represent the concept of either age or transit time. To disambiguate these concepts and propose a metric to assess SOM persistence, we calculated age and transit time distributions for a wide range of soil organic carbon models. Furthermore, we show how age and transit time distributions can be obtained from a stochastic approach that takes a deterministic model of mass transfers among different pools and creates an equivalent stochastic model at the level of atoms. Using this approach we show the following: (1) Age distributions have relatively old mean values and long tails in relation to transit time distributions, suggesting that carbon stored in soils is on average much older than carbon in the release flux. (2) The difference between mean ages and mean transit times is large, with estimates of soil organic carbon persistence on the order of centuries or millennia when assessed using ages and on the order of decades when using transit or turnover times. (3) The age distribution is an appropriate metric to characterize persistence of SOM. An important implication of our analysis is that random chance is a factor that helps to explain why some organic matter persists for millennia in soil. ©2018. The Authors.
英文关键词	biogeochemical cycling; carbon storage; model diagnostics; soil carbon; soil models; time scales
语种	英语
scopus关键词	age structure; biogeochemical cycle; carbon sequestration; model; organic carbon; persistence; soil carbon; soil organic matter; stochasticity; time series analysis
来源期刊	Global Biogeochemical Cycles
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/129782
作者单位	Max Planck Institute for Biogeochemistry, Jena, Germany; Department of Earth System Science, University of California, Irvine, CA, United States
推荐引用方式 GB/T 7714	Sierra C.A.,Hoyt A.M.,He Y.,et al. Soil Organic Matter Persistence as a Stochastic Process: Age and Transit Time Distributions of Carbon in Soils[J],2018,32(10).
APA	Sierra C.A.,Hoyt A.M.,He Y.,&Trumbore S.E..(2018).Soil Organic Matter Persistence as a Stochastic Process: Age and Transit Time Distributions of Carbon in Soils.Global Biogeochemical Cycles,32(10).
MLA	Sierra C.A.,et al."Soil Organic Matter Persistence as a Stochastic Process: Age and Transit Time Distributions of Carbon in Soils".Global Biogeochemical Cycles 32.10(2018).